Life Cycle Assessment of Virtual Mobility. Authors. Uster, June Marianne Leuenberger Rolf Frischknecht ESU-services Ltd.

Transcription

1 Life Cycle Assessment of Virtual Mobility Implemented in ecoinvent data v2.2 (2010) Authors Marianne Leuenberger Rolf Frischknecht ESU-services Ltd. Uster, June 2010 Report ESU-services Ltd. Kanzleistrasse 4 CH Uster Rolf Frischknecht T frischknecht@esu-services.ch Niels Jungbluth T jungbluth@esu-services.ch Sybille Büsser T buesser@esu-services.ch Marianne Leuenberger T leuenberger@esu-services.ch Matthias Stucki T stucki@esu-services.ch F

2 Imprint Title Life Cycle Assessment of Virtual Mobility Authors Marianne Leuenberger, Rolf Frischknecht ESU-services Ltd., fair consulting in sustainability Kanzleistr. 4, CH-8610 Uster Phone , Fax Copyright ESU-services Ltd. owns the life cycle inventory data shown in this study. Liability Statement Information contained herein have been compiled or arrived from sources believed to be reliable. Nevertheless, the authors or their organizations do not accept liability for any loss or damage arising from the use thereof. Using the given information is strictly your own responsibility. Version VM_ecoinvent_report_v1.0.doc, 30 June :59

3 Summary. Summary Videoconferencing and work at home are seen as measures to reduce environmental impact from travel activities. The IT-technology substitutes real mobility by transferring the required data and information through the IP network. Identical to the life cycle inventory of real mobility processes, the infrastructure and the operation thereof are considered to assess the environmental impact of virtual mobility. Acknowledgement We thank Res Witschi and Rolf Schenker (Swisscom) for the information provided on equipment and energy use of Abbreviations and Glossary ADSL DSLAM IP PWB Asymmetric Digital Subscriber Line Digital Subscriber Line Access Multiplexer Internet Protocol Printed Wiring Board - i - ESU-services Ltd.

4 Contents Contents 1 VIRTUAL MOBILITY Introduction Videoconferences Work at home Data sets System description Videoconference Work at home LCI of laptop use LCI of internet devices Network access devices IP core Chassis, network main devices LCI of device use in videoconference, per participant Use of network access devices for a videoconference Use of IP core network for a videoconference LCI of device use for work at home Use of network access devices for work at home Use IP core network for work at home LCI of videoconference and work at home Cumulative results and interpretation Introduction Results Data uncertainty Conclusions References...13 APPENDICES: ECOSPOLD META INFORMATION ii - ESU-services Ltd.

5 1 Virtual Mobility 1.1. Introduction Author: Marianne Leuenberger, Rolf Frischknecht, ESU-services, Uster Review: Christian Bauer, PSI Last changes: Introduction Internet communication technology can substitute travel activity for business purposes. Two types of internet communication are assessed in the following sections: videoconferences and work at home Videoconferences Business meetings often require long distance travelling of one or more participating parties. Similar to traditional telephone conferences current internet technologies allow for videoconferences, which transmit audio and visual data by internet to the members of the meeting. This technology facilitates a more natural interaction between the participants as well as debates on visual matters without the need for actual physical presence in the meeting. Videoconferences therefore can avoid travelling and help reducing the environmental impact of business meetings. However, the infrastructure required for a videoconference and the need for the transmission of large amounts of data may have a considerable environmental impact Work at home Many employees travel a considerable distance to work. In order to reduce the environmental impact of daily commuter traffic, the employees might work some days a week at home. This requires an adequate office environment at the employee s home office. Some companies provide corporate access infrastructure, which makes internal data bases and information accessible from home office workplaces. Corporate access infrastructure bases on special channels that provide a secure data transmission. This additional request for internet infrastructure is taken into account in the life cycle inventory of work at home Data sets The data sets described in this report focus on the use of the devices shown in Fig The use of these devices is calculated for one hour of videoconference or work at home in Switzerland. For instance, the IP network establishes the communication with the server based in the World Wide Web and send queries and answers from and to the user ESU-services Ltd.

6 1.2. System description Fig. 1.1: Devices required for internet communication In order to describe the life cycle inventory of a videoconference, the data sets presented in Tab. 1.1 are established. Tab. 1.1: Overview data sets for virutal mobility (work at home, videoconference) Information Use of laptop computer in home office environment, charged with certified electricity Use of laptop computer in home office environment, charged with supply mix Use of laptop computer in a videoconference, charged with certified electricity Use of laptop computer in a videoconference, charged with supply mix Use of IP core network for data routing during work at home Use of IP core network for data routing in a videoconference Use of network access devices for work at home, using certified electricity Use of network access devices for work at home, using supply mix Use of network access devices for videoconference, using certrified electricity Use of network access devices for videoconference, using supply mix Router used in the IP network Network access devices (ADSL router, modem, DSLAM) Data set name use, computer, laptop, work at home, certified electricity/ch/hr use, computer, laptop, work at home /CH/hr use, computer, laptop, videoconference, certified electricity/ch/hr use, computer, laptop, videoconference, /CH/hr use, IP network, work at home/ch/hr use, IP network, videoconference/ch/hr use, network access devices, certified electricity/ch/hr use, network access devices /CH/hr use, network access devices, certified electricity/ch/hr use, network access devices/ch/hr Router, IP network, at server/ch/unit network access devices, internet, at user/ch/unit 1.2 System description Videoconference The system comprises the end-user devices and the network infrastructure required for data transmission. The included devices consist of the following elements: Laptop with integrated video camera and microphone ESU-services Ltd.

7 1.2. System description Network access devices: ADSL modem with router and DSLAM Server and router for data communication in the IP network Further devices such as beamers and additional cameras or microphones are not included in the data set. The infrastructure for data transmission is a complex structure of routers, servers and cables. An exact mapping is beyond scope, due to the complexity of these transmission systems. We estimate that the environmental impact is mainly influenced by the electricity and material demand of the routers in the system. The number of routers run through by a data package depends on the geographical setting of the videoconference. An average number of 18 routers are assumed 1, which is suitable for data transfer within Switzerland. Functional unit The functional unit is set to one person attending one hour of a business meeting. This allows for comparing videoconferences with traditional business meetings with varying numbers of participants. Scenarios The videoconference is powered by both Swiss supply mix and certified electricity Work at home The system includes the technology required to provide a working environment at the home office equivalent to the one at the company office. Tab. 1.2 describes the infrastructure needed for both working environments. The data set work at home does not consider that a part of the office infrastructure at the company is not used during the time the employee works at home. Furthermore, travel distances saved by working at home are not accounted for. Tab. 1.2: Infrastructure required in company and home office Infrastructure Company office Home office Laptop Standard Standard ADSL-Modem Company capacity Home capacity Router Only for internet access use For company data exchange and internet use DSLAM For internet access use For internet and company intranet access IP-Network Only for internet access use For internet and company intranet access Functional unit The functional unit of the data set of work at home is defined as an average working hour in a home office environment with connection to company internal databases and servers. It is therefore necessary to establish a scenario for an average working hour including database requests, internet research and work based on local data resources. Electricity saved at the company office is not considered. Scenarios The electricity consumption is on one hand covered by the Swiss supply mix and on the other hand by certified electricity. 1 Personal communication, Mr. Res Witschi, , Swisscom, Bern ESU-services Ltd.

8 1.3 LCI of laptop use 1.3. LCI of laptop use The power requirement of a laptop computer depends on its activity. Values during maximum performance can reach up to 40 W. We presume that the power consumption during the transmission of video data is above average and therefore is set to 30 W 2. The average use modes for a working day are derived from the EPIC study (EPIC_ICT 2003), which was applied for the average laptop use in offices. As the functional unit of work at home is set to one working hour, the work at home data set only considers the mode mix during 8 working hours (see Tab. 1.3). In the ecoinvent report on the use of electronic devices (Hischier et al. 2007) the following values are provided: Tab. 1.3: Power requirement of a laptop computer (Hischier et al. 2007) Modes Range (Literature study) ecoinvent values % whole day (EPIC_ICT) % working hours (own calculation) Active mode W 19 W 20.83% (5.5h) 68.75% (5.5h) Standby/sleep mode W 4 W 8.33% (2h) 25% (2h) Off mode W 2 W 70.83% (16.5h) 6.25% (0.5h) For the laptop used for work at home we assume the same hours for the active or standby mode as given in the EPIC_ICT model above. Half an hour per working day are accounted for as off mode, which represents non-computer based work (literature study, meetings or telephone calls). Further equipment is not accounted for, as it is assumed that current laptop models contain a video camera and microphone to set up a videoconference. The laptop is being used during four years and 1850 hours. Transport is included for rail and lorry transport from the plant to the customer (see Tab. 1.3). The applied values correspond to the ecoinvent data (Frischknecht et al. 2007). Tab. 1.4: Unit process raw data of laptop use for work at home and videoconference Name Location InfrastructureP Unit use, computer, laptop, work at home use, computer, laptop, work at home, certified electricity mix use, computer, laptop, videoconference use, computer, laptop, videoconference, certified electricity mix Location CH CH CH CH InfrastructureProcess Unit h h h h product use, computer, laptop, work at home CH 0 h use, computer, laptop, work at home, certified electricity CH 0 h use, computer, laptop, videoconference CH 0 h use, computer, laptop, videoconference, certified electricity mix CH 0 h UncertaintyTyp e StandardDevia tion95% GeneralComment technosphere laptop computer, at plant GLO 0 unit 1.35E E E E (2,3,2,2,1,4); lifttime: 4 years and 1850 hours electricity, low voltage, consumer mix, at grid CH 0 kwh 1.42E E electricity, low voltage, certified, at grid CH 0 kwh 1.42E E transport, freight, rail RER 0 tkm 1.80E E E E transport, lorry >16t, fleet average RER 0 tkm 8.59E E E E (2,2,1,1,1,4); according to ecoinvent report no. 18: 12.75% ff: 2W, 25%standby: 4W, 68.75% active:19w, 100%video: 30W (2,2,1,1,1,4); according to ecoinvent report no. 18: 12.75% ff: 2W, 25%standby: 4W, 68.75% active:19w, 100%video: 30W (2,3,1,3,3,5); according to ecoinvent report no.18, section (2,3,1,3,3,5); according to ecoinvent report no.18, section Personal communication R. Witschi, Swisscom, ESU-services Ltd.

9 1.4 LCI of internet devices Network access devices 1.4. LCI of internet devices The internet connection of computers requires several devices for communication and guidance of the information through the network. Most commonly, a modem and a router are connected to the local network or computer. The current technology involves a Digital Subscriber Line (DSL) connection to broadband internet. It can be installed on analogue (POTS) or digital (ISDN) telephone connections. Because the DSL technology uses the telephone line for data transmission, a splitter is introduced to split telephone information from internet data transmission. The majority of the modems include a router, which sorts the incoming and outgoing data and sends them to the correct destination. The following network access devices are taken into account: - ADSL modem with router - DSLAM Splitters are excluded from the LCI because they are passive modules without electricity demand and often are part of the routing devices. The LCI data representing the DSLAM is taken from the factsheet of the Zyxel IES-6000 Series DSLAM, which contains ports for 768 users (ZyXel 2009). The material use for the devices manufacture is roughly estimated based on weight and dimensions of the devices. The chassis dataset accounts for plastics and metals input, whereas the printed wiring board represents the electronic equipment of the devices. Further specifications are presented in Tab IP core The Internet Protocol (IP) network provides the infrastructure for data transmission in the internet. The information is introduced to the IP-network by a digital subscriber line access multiplexer DSLAM. The DSLAM is the link between the local and the global IP network, which sends or receives data to or from a regional broadband remote access server. In order to reach the point of destination, the data is routed from the entry of the IP network to further servers according to its IP address. Usually, the data package passes several routers on the way to its destination. The number of routers run through by a data package depends on several factors one of which is the geographical distance between the two points of communication. Other factors are difficult to quantify and are partly subject to random. The data set router, IP core network, describes the composition of a commonly used router. The data for the material use of IP core is estimated using product information on weight and printed wiring board area of a Cisco Service Routers 1800 Series (Cisco Systems 2009). The specifications are listed in Tab Chassis, network main devices Data on the production and composition of a chassis in are scarce. The broad variety of leads to many different shares of material inputs. The values used for the data set chassis, network main devices represent an estimation of the average input materials derived from factsheets (Cisco Systems 2009; ZyXel 2009) and the estimation of other electronic (GSM base station, inverse rectifier). Main components are steel (62%) and copper (15%). The processing of these materials is taken into account by sheet rolling, powder coating and wire drawing (see Tab. 1.5) ESU-services Ltd.

10 1.4. LCI of internet devices Tab. 1.5: Unit process raw data of chassis, network main devices Name Location InfrastructurePr Unit chassis, network main devices UncertaintyTyp e StandardDeviati on95% GeneralComment Location RER InfrastructureProcess 0 Unit kg product chassis, network main devices RER 0 kg 1 technosphere electricity, low voltage, production UCTE, at grid UCTE 0 kwh 1.00E aluminium, production mix, cast alloy, at plant RER 0 kg 2.50E aluminium, production mix, at plant RER 0 kg 2.50E cast iron, at plant RER 0 kg 5.00E copper, at regional storage RER 0 kg 1.50E steel, low-alloyed, at plant RER 0 kg 6.22E tin, at regional storage RER 0 kg 2.00E brass, at plant CH 0 kg 1.00E zinc, primary, at regional storage RER 0 kg 1.00E epoxy resin, liquid, at plant RER 0 kg 2.00E polyethylene, HDPE, granulate, at plant RER 0 kg 1.00E polyvinylchloride, bulk polymerised, at plant RER 0 kg 1.00E polypropylene, granulate, at plant RER 0 kg 5.00E flat glass, coated, at plant RER 0 kg 2.00E silicone product, at plant RER 0 kg 1.00E corrugated board, mixed fibre, single wall, at plant RER 0 kg 4.00E (5,na,2,3,3,na); packaging transport, lorry >16t, fleet average RER 0 tkm 1.00E (5,na,2,3,3,na); standard distance 100km transport, freight, rail RER 0 tkm 2.00E (5,na,2,3,3,na); standard distance 200km transport, lorry t, fleet average RER 0 tkm 5.00E (5,na,2,3,3,na); delivery to storage 500km transport, van <3.5t RER 0 tkm 3.00E (5,na,2,3,3,na); installation, service, deinstallation 300km sheet rolling, steel RER 0 kg 6.22E powder coating, steel RER 0 m2 5.00E wire drawing, copper RER 0 kg 1.50E disposal, building, bulk iron (excluding reinforcement), to sorting plant CH 0 kg 6.72E disposal, packaging cardboard, 19.6% water, to municipal incineration CH 0 kg 4.00E disposal, plastic, industr. electronics, 15.3% water, to municipal incineration CH 0 kg 1.10E emission air, high population Heat, waste - - MJ 3.60E (3,na,1,1,1,na); calculation Tab. 1.6: Specifications of network access and IP core Weights of devices without PWB Unit Core network Access router devices Source ADSL modem with router kg 2.40E-01 Estimation, total weight from factssheet Zyxel DSLAM per port kg 3.91E-02 Factssheet Zyxel IES-6000 Series: 15 kg / 768 ports, 50% utilisation Core network router kg 1.82E+00 Cisco router factssheet: 3.63 kg, assumption PWB=50% of weight Area of PWB Unit Core network Access router devices ADSL modem with router m2 1.40E-02 Estimation DSLAM m2 3.96E-03 Factssheet Zyxel IES-6000 Series: 39.6x24cm per 48 ports, 50% utilisation Core network router m2 7.49E-02 Cisco router factssheet: area 26.67cmx28.07cm Parts Unit Core network Access router devices Source total weight of device withouth PWB kg 1.82E E-01 Sum of ADSL modem/router and DSLAM area of wiring board m2 7.49E E-02 Sum of ADSL modem/router and DSLAM ESU-services Ltd.

11 1.5. LCI of device use in videoconference, per participant Tab. 1.7: Unit process raw data of network access devices Name Location InfrastructureP Unit router, IP network, at server network access devices, internet, at user Location CH CH InfrastructureProcess 1 1 Unit unit unit product router, IP network, at server CH 1 unit 1 0 network access devices, internet, at user CH 1 unit 0 1 technosphere chassis, network main devices RER 0 kg 1.82E E technosphere printed wiring board, surface mount, at plant GLO 0 m2 7.49E E UncertaintyTyp e StandardDevia tion95% transport, transoceanic freight ship OCE 0 tkm 4.36E E transport, lorry t, fleet average RER 0 tkm 2.90E E GeneralComment (4,3,2,1,4,4); Estimation, total weight from factssheet Zyxel; Factssheet Zyxel IES-6000 Series: 15 kg / 768 ports, 50% utilisation; Cisco router factssheet: 3.63 kg, assumption PWB=50% of weight (4,3,2,1,4,4); Estimation; Factssheet Zyxel IES-6000 Series: 39.6x24cm per 48 ports, 50% utilisation; Cisco router factssheet: area 26.67cmx28.07cm (2,3,1,3,3,4); Over all weight of device = 2* chassis weight, transport from Asia: 12000km (2,3,1,3,3,4); Over all weight of device = 2* chassis weight, transport from Rotterdam: 800km 1.5 LCI of device use in videoconference, per participant For one hour of videoconference the material share and the electricity consumption of the involved devices are taken into account. The material includes one laptop equipped for videoconferencing, one set of network access devices and an average core network device per participant. As the data transmission is mutual, the IP network use is equal for all participants. The videoconference usally includes 3 to 5 participants. This can be modelled by multiplying the LCA results for one participant by the number of participants. The electricity used in the network access devices is either Swiss supply mix or certified electricity. The electricity used in the core network is Swiss supply mix, because the majority of the core network devices run on non-certified electricity Use of network access devices for a videoconference The life expectancies of the ADSL modem/router and the DSLAM are set to 6 years (1850 working hours each). The ADSL router demands kwh per hour, when constantly working at full load. The difference of electricity consumption between full load and standby mode is marginal and therefore neglected. Similarly, for the DSLAM only average values of electricity consumption are available, which is kwh per port. The data sets use either the Swiss supply mix, or certified electricity, which consists of electricity from renewable energy sources. The electricity conversion to 48V has an estimated efficiency of 90%. Tab. 1.8: Electricity consumption of network access devices Electricity demand of access devices Unit Videoconference Work at home Source DSLAM, power consumption per port kw Personal communication Witschi (2009) DSLAM capacity utilization % Personal communication Witschi (2009) ADSL router+modem power consumption full load kw Assumptions based on unpublished report Conversion efficieny % Calculation Use of IP core network for a videoconference The material share is calculated for all using the lifetime of the device (6 years) and the annual hours in use (8760 hours). We assume that the core are used 24 hours per day. Additionally, the material share is divided in proportion to the actually used bandwidth for the videoconference. The router data set represents a router with an average used bandwidth of 25 MBit/s. The share is calculated using the data exchange of the specific activity. The data packages run through ESU-services Ltd.

12 1.6. LCI of device use for work at home 18 routers on their way between the participants of the conference and require a bandwidth of 0.7 MBit/s. Tab. 1.9: Values used for the calculation of the share of the IP core network router infrastructure for a videoconference Information Values Life time of IP core network device 6 years Annual hours 8760 hours Total hours in operation hours Number of routers run through by data package 18 Average bandwidth in use in an IP router 25 MBit/s Bandwidth demanded for videoconferencing 0.7 MBit/s Amount of data exchange 315 Mbytes/hour Experts estimate an electricity demand of kwh per hour at a bandwidth of 1 MBit/s (Witschi 2009). Depending on the utilised capacity of the router the electricity demand per data amount can vary widely. Small servers with a low efficiency achieve values of 8.5 kwh at 1MBit/s. On the other hand, a larger server with full capacity load consumes only kwh at 1MBit/s. The electricity consumption used for this data set is kwh per hour at a data flow rate of 1MBit/s. The electricity consumption is calculated extrapolating the average electricity demand of kwh per IP router at 1 MBit/s for the actually required bandwidth of 0.7 MBit/s for the videoconference. This corresponds to 315 Mbytes data transferred per hour. We estimate that the electricity demand is correlated linearly to the used bandwidth or amount of data in transfer. Furthermore, the routers have a high energy demand for cooling, which additionally increases the electricity demand of data routing by factor % of the electricity is lost by electricity conversion. Tab. 1.10: Electricity demand of IP core for videoconference use Electricity demand of IP core Unit Videoconference Source Power demand of core network router at 1Mbit/s kw Personal communication Witschi (2009) Electricity consumption at 0.7 Mbit/s bandwidth kwh Calculation Indirect electricity use of IP core Indirect electricity use for cooling per kwh kwh 0.5 Personal communication Witschi (2009) 1.6 LCI of device use for work at home Work at home requires a laptop computer connected to the company s server by internet. The internet access is provided by a set of network access devices. Depending on the working activities, the data transfer between the company server and the laptop varies considerably. For an average work at home scenario, the following assumptions are taken: - data transfer during 30 minutes in one working hour - the amount of data exchanged is comparable to the data load of an average internet search (24kB/s) - modest activity (256 kb/hr) 3 Personal communication R. Witschi, Swisscom, Bern, ESU-services Ltd.

13 1.6. LCI of device use for work at home The electricity used in the network access devices is either Swiss supply mix or certified electricity. The electricity used in the core network is Swiss supply mix, because the majority of the core network devices run on non-certified electricity Use of network access devices for work at home The data set for the network access device is independent of the bandwidth used for the communication service. The network access device use for work at home is therefore identical to the use in videoconferences (see Section 1.5.1) Use IP core network for work at home The material share is calculated using the lifetime of the devices (6 years) and the hours in use (8760). It is assumed that all devices are used 24 hours a day. For the IP core network router, the material share depends on the amount of data exchange. The router data set represents a router with an average real load of 25 MBit/s. The share is calculated using the data exchange of the specific activity. The data packages run through 18 routers on their way between the company and the home office at a bandwidth of 0.2 MBit/s for average internet use and communication. Tab. 1.11: Values used for the calculation of the share of the IP core network router infrastructure for work at home Information Values Life time of IP core network device 6 years Annual hours 8760 hours Total hours in operation hours Number of routers run through by data package 18 Average bandwidth in use inan IP router 25 MBit/s Bandwidth demanded for videoconferencing 0.2 MBit/s Amount of data exchanged 90 Mbytes/hour Internet use 50% of working hour The electricity consumption is calculated extrapolating the average electricity consumption of kwh per IP router at 1 MBit/s for the bandwidth of 0.2 MBit/s, which corresponds to 90 Mbytes data transfer per hour. The routers have a high energy demand for cooling, which additionally increases the electricity demand of data routing by factor 1.5 (see Tab. 1.12) ESU-services Ltd.

14 1.6. LCI of device use for work at home Tab. 1.12: Electricity demand of the IP core for work at home Electricity demand of IP core Unit Work at home Source Power demand of core network router at 1Mbit/s kw Personal communication Witschi (2009) Electricity consumption at 24 kbytes/s kwh 8.06E-04 Calculation Indirect electricity use of IP core Indirect electricity use for cooling per kwh kwh 0.5 Personal communication Witschi (2009) Tab. 1.13: Unit process raw data of IP core network and access devices for one hour of videoconference and work at home Name Unit use, IP network, use, IP network, videoconferenc work at home e use, network access devices use, network access devices, certified electricity mix Location CH CH CH CH InfrastructureProcess Unit h h h h 4 use, IP network, videoconference h use, IP network, work at home h use, network access devices h use, network access devices, certified electricity mix h technosphere network access devices, internet, at user unit 9.01E E UncertaintyTyp e StandardDevia tion95% GeneralComment (4,3,1,1,3,4); 1 ADSL modem/router, DSLAM per port router, IP network, at server unit 9.59E E (4,3,1,1,3,4); 18 routers bandwidth 25MBits electricity, low voltage, consumer mix, at grid kwh 8.82E E E electricity, low voltage, certified, at grid kwh 7.56E (4,3,1,1,3,4); Electricity demand: 4.2Wh ADSL, 1.3Wh DSLAM per port, 4.2Wh/Router at 1MBit/s (4,3,1,1,3,4); Electricity demand: 4.2Wh ADSL, 1.3Wh DSLAM per port, 4.2Wh/Router at 1MBit/s ESU-services Ltd.

15 1.7. LCI of videoconference and work at home 1.7 LCI of videoconference and work at home The life cycle inventories of videoconference and work at home combine the use of the different devices used for communication services. Both data sets include the use of one laptop, one set of network access device and one set of IP core network routers. However, they differ in the electricity consumption due to the different use of bandwidth. For both communication services the Swiss supply mix on one hand and certified electricity on the other cover the electricity demand of the laptop and the network access devices. In order to assess the environmental impact of a videoconference with two or more participants, the LCA results of the videoconference data set can be multiplied by the number of participants. Tab. 1.14: Unit process raw data of work at home Name Location InfrastructureProcess Unit work at home, corporate access work at home, corporate access, certified electricity mix videoconference, laptop, participant videoconference, laptop, participant, certified electricity mix UncertaintyType StandardDeviation95 % GeneralComment Location CH CH CH CH InfrastructureProcess Unit h h h h work at home, corporate access CH 0 h work at home, corporate access, certified electricity mix CH 0 h videoconference, laptop, participant CH 0 h videoconference, laptop, participant, certified electricity mix CH 0 h technosphere use, computer, laptop, videoconference CH 0 h 1.00E+0 1 (4,3,1,1,1,4); 1 hour laptop use according to 2.06 user profile use, computer, laptop, videoconference, certified electricity (4,3,1,1,1,4); 1 hour laptop use according to CH 0 h 1.00E mix user profile use, computer, laptop, work at home CH 0 h 1.00E+0 1 (4,3,1,1,1,4); 1 hour laptop use according to 2.06 user profile use, computer, laptop, work at home, certified electricity (4,3,1,1,1,4); 1 hour laptop use according to CH 0 h 1.00E mix user profile use, IP network, videoconference CH 0 h 1.00E E+0 1 (4,3,1,1,1,4); 1 hour IP router use according to 2.06 user profile use, IP network, work at home CH 0 h 1.00E E+00 1 (4,3,1,1,1,4); 1 hour IP router use according to 2.06 user profile use, network access devices CH 0 h 1.00E E+0 1 (4,3,1,1,1,4); 1 hour network access device 2.06 use according to user profile use, network access devices, certified electricity mix CH 0 h 1.00E E+0 1 (4,3,1,1,1,4); 1 hour network access device 2.06 use according to user profile ESU-services Ltd.

16 1.8. Cumulative results and interpretation 1.8 Cumulative results and interpretation Introduction Selected LCI results and values for the cumulative energy demand are presented and discussed in this chapter. Please note that only a small part of the about 1'000 elementary flows is presented here. The selection of the elementary flows shown in the tables is not based on their environmental relevance. It rather allows to show by examples the contributions of the different life cycle phases, or specific inputs from the technosphere to the selected elementary flows. Please refer to the ecoinvent database for the complete LCIs. The shown selection is not suited for a life cycle assessment of the analysed processes and products. Please use the data downloaded from the database for your own calculations, also because of possible minor deviations between the presented results and the database due to corrections and changes in background data used as inputs in the dataset of interest. The ecoinvent database also contains life cycle impact assessment results. Assumptions and interpretations were necessary to match current LCIA methods with the ecoinvent inventory results. They are described in Frischknecht et al. (2007). It is strongly advised to read the respective chapters of the implementation report before applying LCIA results Results Tab shows selected LCI results and the cumulative energy demand for the videoconferences and work at home. The use of non-renewable energy sources is higher for the processes, in which the devices run on supply mix. Reciprocally, the consumption of renewable energy is higher in processes using certified electricity. However, the difference between the processes is rather small, as the main energy demand arises from the production of the devices and the IP core network, which runs on supply mix in both cases. Air emissions, such as CO 2 or NMVOC, arise from the electricity production and therefore their variation among the processes is similar to the variation of the energy demand. The emissions of BOD and Cadmium vary only slightly, which shows that the manufacture of the equipment contributes significantly to these emissions. Tab Selected LCI results and the cumulative energy demand of videoconference and work at home Name videoconferen ce, laptop, participant, certified electricity videoconferen ce, laptop, participant, consumer mix work at home, corporate access, certified electricity work at home, corporate access, consumer mix Location CH CH CH CH InfrastructureProcess Unit Unit hr hr hr hr CED Non renewable, fossil MJ eq 4.34E E E E-1 CED Non-renewable, nuclear MJ eq 7.23E E E E-1 CED Non-renewable, biomass MJ eq 1.28E E E E-6 CED Renewable, biomass MJ eq 2.17E E E E-2 CED Renewable, wind, solar, geothe MJ eq 5.86E E E E-3 CED Renewable, water MJ eq 3.21E E E E-2 NMVOC air kg 2.00E E E E-5 Carbon dioxide, fossil air kg 3.47E E E E-2 Sulphur dioxide air kg 1.49E E E E-4 Nitrogen oxides air kg 8.51E E E E-5 Particulates, <2.5 um air kg 1.30E E E E-6 Land occupation resource m2a 2.81E E E E-3 BOD water kg 1.86E E E E-4 Cadmium soil kg 7.58E E E E ESU-services Ltd.

17 1.9. Conclusions Data uncertainty The data uncertainty mainly arises from production und the energy consumption of. Many different types of servers and routers with various capacities lead to a high variation of energy consumption and material input for these devices. Additionally, the number of routers used in the IP core network varies. The material composition of is based on rough assumptions and does not accurately represent the chassis of the devices. 1.9 Conclusions Virtual mobility substitutes travel by using IT-technology for the transfer of information. This office environment and the home office environment basically only differ in the use of an additional laptop and internet connection. Similarly, the videoconference can be held with a laptop per participant and a broadband internet connection. For both processes, the technical effort can be augmented to special connection to the company server or telepresence meetings with highly developed audiovisual equippement. Considering the substituted travel activity, which is not specifically accounted for in the data set, the environmental impact of work at home could be considerably lower than the one assessed with this data set. The selected LCI results show, that the energy demand of the IT-infrastructure operation and the manufacture of the equipment have a considerable influence on the environmental impact of virtual mobility. The selection of the equipment and the data amount are therefore considered to be the key factors References Cisco Systems 2009 Cisco Systems (2009) Cisco 1861 Integrated Services Router. Retrieved retrieved from: EPIC_ICT 2003 Frischknecht et al Hischier et al Witschi 2009 ZyXel 2009 EPIC_ICT (2003) Development of Environmental Performance Indicators for ICT Products on the example of Personal Computers. EU/FP6. European Commission, Brussels. Frischknecht R., Jungbluth N., Althaus H.-J., Bauer C., Doka G., Dones R., Hellweg S., Hischier R., Humbert S., Margni M. and Nemecek T. (2007) Implementation of Life Cycle Impact Assessment Methods. ecoinvent report No. 3, v2.0. Swiss Centre for Life Cycle Inventories, Dübendorf, CH, retrieved from: Hischier R., Classen M., Lehmann M. and Scharnhorst W. (2007) Life Cycle Inventories of Electric and Electronic Equipment - Production, Use & Disposal. ecoinvent report No. 18, v2.0. EMPA St. Gallen, Swiss Centre for Life Cycle Inventories, Dübendorf, CH, retrieved from: Witschi R. (2009) Abschätzungen Router und Stromverbrauch bei Videokonferenz und work@home. (ed. Leuenberger M.). Swisscom, Bern. ZyXel (2009) IP DSLAM IES-6000 Series 12.5U High Capacity Multi-Service Access Node. Retrieved retrieved from: ESU-services Ltd.

18 Appendices: EcoSpold Meta Information Appendices: EcoSpold Meta Information Tab. A. 1 EcoSpold Meta Information of laptop use in videoconferences and for work at home ReferenceFunction Name use, computer, laptop, work at home use, computer, laptop, work at home, certified electricity mix use, computer, laptop, videoconference use, computer, laptop, videoconference, certified electricity mix Geography Location CH CH CH CH ReferenceFunction InfrastructureProcess ReferenceFunction Unit h h h h IncludedProcesses LocalName the use of a laptop and the energy consumption for working at home. It includes the laptop production, transport from plant to customer and electricity consumption (from consumer mix) for average office work. Nutzung, Computer, Laptop, Heimarbeit the use of a laptop and the energy consumption for working at home. It includes the laptop production, transport from plant to customer and electricity consumption (from certified electricity) for average office work. Nutzung, Computer, Laptop, Heimarbeit, zertifizierter Strom Synonyms Heimarbeit Heimarbeit GeneralComment the use of a laptop computer during work at home. the use of a laptop computer during work at home. the use of a laptop and the energy consumption for a videoconference. It further includes the laptop production and transport from plant to customer). Nutzung, Computer, Laptop, Videokonferenz the use of a laptop computer during a videoconference. An average electricity consumption of 30W is set (Swiss consumer mix). InfrastructureIncluded Category electronics electronics electronics electronics SubCategory services services services services LocalCategory Elektronik Elektronik Elektronik Elektronik the use of a laptop and the energy consumption for a videoconference. It further includes the laptop production and transport from plant to customer). Nutzung, Computer, Laptop, Videokonferenz, zertifizierter Strom the use of a laptop computer during a videoconference. An average electricity consumption of 30W is set (certified electricity mix). LocalSubCategory Dienstleistung Dienstleistung Dienstleistung Dienstleistung Formula StatisticalClassification CASNumber TimePeriod StartDate EndDate DataValidForEntirePeriod OtherPeriodText Geography Text Data for Swiss conditions Data for Swiss conditions Data for Swiss conditions Data for Swiss conditions Work at home using an Work at home using an average laptop computer average laptop computer Laptop use in Laptop use in Technology Text with 68% active mode, with 68% active mode, videoconferences, 100% videoconferences, 100% 25%standby mode and 25%standby mode and video mode (30W) video mode (30W) 6% off mode 6% off mode Representativeness Percent ProductionVolume unknown unknown unknown unknown SamplingProcedure unknown unknown unknown unknown Extrapolations Average technology Average technology Average technology Average technology UncertaintyAdjustments none none none none ESU-services Ltd.

19 Appendices: EcoSpold Meta Information Tab. A. 2 EcoSpold Meta Information of router and network access devices, at user ReferenceFunction Name router, IP network, at network access devices, server internet, at user Geography Location CH CH ReferenceFunction InfrastructureProcess 1 1 ReferenceFunction Unit unit unit IncludedProcesses LocalName Synonyms GeneralComment This data sets represents an IP core network router. Manufacture and transport included. Router, IP Netz, in Server an average IP core network device, based on assumption for the chassis and PWB. InfrastructureIncluded 1 1 Category electronics electronics SubCategory devices devices LocalCategory Elektronik Elektronik LocalSubCategory Geräte Geräte Formula StatisticalClassification CASNumber TimePeriod StartDate EndDate DataValidForEntirePeriod 1 1 OtherPeriodText all network access devices usually required for internet communication. It namely includes: ADSL modem with router, DSLAM and connecting cables. Manufacture and transport included. Netzwerkzugangsgeräte, Internetverbindung, bei Benutzer the material in internet access devices, based on assumptions for the chassis and PWB. Geography Text Data for Swiss conditions Data for Swiss conditions Technology Text IP core network device (IP router) derived from Cisco Service Router 1800 Series, maximal data rate: 100 Mbit/s, realistic: 25 Mbit/s. Power demand: kw at 1 Mbit/s. Included devices: ADSL modem with router and DSLAM, DSLAM with 17 line cards with 48 ports. 50% capacity utilisation. Representativeness Percent ProductionVolume unknown unknown SamplingProcedure unknown unknown Extrapolations Average technology Average technology UncertaintyAdjustments none none ESU-services Ltd.

20 Appendices: EcoSpold Meta Information Tab. A. 3 EcoSpold Meta Information of chassis, main network device ReferenceFunction Name chassis, network main devices Geography Location RER ReferenceFunction InfrastructureProcess 0 ReferenceFunction Unit kg IncludedProcesses materials, standard transport distances, electricity use for manufacturing, disposal Amount 1 LocalName Gehäuse, Netzwerk Gerät Synonyms GeneralComment Rough assumption based on previous study for telecom equipment and personal communication with experts. InfrastructureIncluded 1 Category electronics SubCategory component LocalCategory Elektronik LocalSubCategory Bauteile Formula StatisticalClassification CASNumber TimePeriod StartDate 2000 EndDate 2009 DataValidForEntirePeriod 1 OtherPeriodText Geography Text Switzerland Technology Text average material composition of chassis for. Life expectancy: 6 years, annual working hour depending on use. Representativeness Percent ProductionVolume unknown SamplingProcedure expert guess, factsheets Extrapolations none UncertaintyAdjustments none ESU-services Ltd.

21 Appendices: EcoSpold Meta Information Tab. A. 4 EcoSpold Meta Information of IP network and network access devices use ReferenceFunction Name use, IP network, videoconference use, IP network, work at home use, network access devices use, network access devices, certified electricity mix Geography Location CH CH CH CH ReferenceFunction InfrastructureProcess ReferenceFunction Unit h h h h IncludedProcesses LocalName Synonyms GeneralComment the use of the IP core network for videoconference (0.7 Mbit/s) data exchange for one hour, taking into account IP router use and electricity consumption. Nutzung, IP Netz, Videokonferenz average values for one hour of IP network use during a videoconference per participant the use of the IP core network for work at home data exchange (0.2 Mbit/s) for one hour taking into account IP router use and electricity consumption. Nutzung, IP Netz, Heimarbeit average values for one hour of IP network use for work at home per person the use of internet access devices for one end user during one hour, taking into account device use and electricity consumption (consumer mix) Nutzung, Netzwerkzugangsgeräte average values for one hour use of network access devices per work station. InfrastructureIncluded Category electronics electronics electronics electronics SubCategory services services services services LocalCategory Elektronik Elektronik Elektronik Elektronik the use of internet access devices for one end user during one hour, taking into account device use and electricity consumption (certified electricity mix) Nutzung, Netzwerkzugangsgeräte, zertifizierter Strom average values for one hour use of network access devices per work station. LocalSubCategory Dienstleistung Dienstleistung Dienstleistung Dienstleistung Formula StatisticalClassification CASNumber TimePeriod StartDate EndDate DataValidForEntirePeriod OtherPeriodText Geography Text Data for Swiss conditions Data for Swiss conditions Data for Swiss conditions Data for Swiss conditions Technology Representativeness Text IP core network device (IP router) derived from Cisco Service Router 1800 Series, maximal data rate: 100 Mbit/s, realistic: 25 Mbit/s. Power demand: kw at 1 Mbit/s. Band width for videoconference: 0.7Mbit/s IP core network device (IP router) derived from Cisco Service Router 1800 Series, maximal data rate: 100 Mbit/s, realistic: 25 Mbit/s. Power demand: kw at 1 Mbit/s. Band width for work at home: 0.2Mbit/s Included devices: ADSL modem with router (0.0042kW) and DSLAM ( kw) per end user Included devices: ADSL modem with router (0.0042kW) and DSLAM ( kw) per end user Percent ProductionVolume unknown unknown unknown unknown SamplingProcedure unknown unknown unknown unknown Extrapolations Average technology Average technology Average technology Average technology UncertaintyAdjustments none none none none ESU-services Ltd.

22 Appendices: EcoSpold Meta Information Tab. A. 5 EcoSpold Meta Information of videoconference and work at home ReferenceFunction Name work at home, corporate access work at home, corporate access, certified electricity mix videoconference, laptop, participant videoconference, laptop, participant, certified electricity mix Geography Location CH CH CH CH ReferenceFunction InfrastructureProcess ReferenceFunction Unit h h h h IncludedProcesses LocalName Synonyms GeneralComment the use of hardware (laptop, internet devices) and energy consumption for on hour work at home using broadband access to company server. Consumer mix electricity consumption. Heimarbeit, Corporate Access average values for one hour of work at home using a laptop computer. The data set does not the use of hardware (laptop, internet devices) and energy consumption for on hour work at home using broadband access to company server. certified electricity consumption. Heimarbeit, Corporate Access, zertifizierter Strom average values for one hour of work at home using a laptop computer. The data set does not account for energy saved account for energy saved at the company work at the company work place and avoided place and avoided travelling. travelling. the use of hardware (laptop, internet devices) and energy consumption for on hour videoconference using broadband access per participant. Consumer mix electricity consumption. Videokonferenz, Laptop, Teilnehmer average values for one videoconference using a laptop computer. InfrastructureIncluded Category electronics electronics electronics electronics SubCategory services services services services LocalCategory Elektronik Elektronik Elektronik Elektronik the use of hardware (laptop, internet devices) and energy consumption for on hour videoconference using broadband access per participant. Certified mix electricity consumption. Videokonferenz, Laptop, Teilnehmer, zertifizierter Strom average values for one videoconference using a laptop computer. LocalSubCategory Dienstleistung Dienstleistung Dienstleistung Dienstleistung Formula StatisticalClassification CASNumber TimePeriod StartDate EndDate DataValidForEntirePeriod OtherPeriodText Geography Text Data for Swiss conditions Data for Swiss conditions Data for Swiss conditions Data for Swiss conditions Technology Text Work at home using a laptop computer and broadband transmission for data exchange. Consumer mix electricity. Calculated for 1850 annual working hours, 50% internet use, band width: 0.2 Mbit/s Work at home using a laptop computer and broadband transmission for data exchange. Certified mix electricity. Calculated for 1850 annual working hours, 50% internet use, band width: 0.2 Mbit/s videoconference using laptops and cameras for image and sound transmission. Band width: 0.7MBit/s. Consumer mix electricity consumption. videoconference using laptops and cameras for image and sound transmission. Band width: 0.7MBit/s. Consumer mix electricity consumption. Representativeness Percent ProductionVolume unknown unknown unknown unknown SamplingProcedure unknown unknown unknown unknown Extrapolations Average technology Average technology Average technology Average technology UncertaintyAdjustments none none none none ESU-services Ltd.